IWOMC

It Works On My Computer. IWOMC finds out why, and fixes it.

Your teammate clones the commit you just pushed. Your app runs. Theirs does not. Usually the difference is not in the code - it is on your disk. A package that got installed but never added to package.json. A version that had to be rolled back. A virtual environment set up by hand weeks ago.

IWOMC records what your machine actually has, ties it to the exact Git commit, and uses that to make the other machine work - then proves it by running your own test command. It says working only when that command passes.

Install

npm install -g iwomc

Node.js 22.5 or newer. No Docker, no account, no server.

Use it

On the checkout that works:

iwomc init --proof "npm test"
iwomc capture
iwomc verify

On the checkout that is broken:

iwomc rescue --approve

Then, so nobody hits it again:

iwomc promote          # show an ordinary diff that fixes the repository
iwomc promote --apply

Keep a history

A contract describes one commit. To answer what was installed at 2pm last Tuesday

• or to catch a downgrade, which a snapshot cannot express - leave the recorder on:

iwomc daemon status                       # a recorder starts by itself; this shows it
iwomc timeline <commit>                   # what was installed at that commit
iwomc diff <their-commit> <your-commit>   # what is different between the two

The recorder starts the first time you use IWOMC in a project and tells you it has. It reads your project's package folders and nothing else: it never runs a package manager, never looks outside the projects you registered, never edits a tracked file, and never uploads your history. iwomc daemon disable stops it.

For coding agents

iwomc mcp exposes the same workflow as typed MCP tools. Anything that changes your machine refuses to run without explicit confirmation. Run iwomc agent-docs for the full reference offline.

Across operating systems

The person whose machine works is often not on your operating system. IWOMC applies their contract anyway when nothing in it is restricted to one platform, and says it was proven elsewhere rather than implying otherwise. When something is restricted - a build tool's per-platform binary, say - it refuses and names the package instead of giving you a generic mismatch to diagnose.

Supported today

Nine package managers are detected, recorded, repaired, and verified:

| Ecosystem | Managers | | --- | --- | | Node.js | npm, pnpm, Yarn, Bun | | Python | pip, uv, Poetry | | Rust | Cargo | | Go | Go modules |

Every one of them installs inside your project folder only. Each keeps a machine-wide cache by default - ~/.cargo, ~/.npm, Go's module cache - and IWOMC redirects every one into the project's own .iwomc directory, so a rescue never changes anything outside the checkout it was pointed at.

Cargo and Go find their dependencies only through an environment variable. IWOMC sets it for the proof command it runs and prints what to set in your own shell; it cannot change your shell for you.

Nineteen more are recognised and reported honestly as not yet repairable, rather than claimed as supported. iwomc status names the level for the project you are in.

More

Source, documentation, and issues: https://github.com/Carldtitan/Environment_Drift

MIT licensed.